Separately, coffee’s beneficial effects on gut health, brain and mood have been extensively studied, but recent research suggests that coffee may have a positive effect on the gut-brain axis.
The gut-brain axis is a bidirectional communication between the gut microbiome and the brain, allowing the gut to influence factors such as mood and stress levels. In a recent study published in the journal Scientists from APC Microbiome Ireland at University College Cork sought to investigate how coffee affects the gut-brain axis.
For their research, per Independentresearchers followed 31 regular coffee drinkers – defined as people drinking three to five cups of coffee a day – and 31 non-coffee drinkers over a two-year period. Before the study, participants were asked to refrain from drinking coffee for two weeks. During this time, participants were subjected to regular psychological tests and urine and stool samples were collected. When the initial samples were examined, researchers found “significant changes” in the number of compounds produced by non-coffee drinkers’ gut bacteria that support with metabolism and digestion.
After the initial assessment, coffee drinkers were assigned to one of two groups: decaffeinated and regular coffee; participants were not aware which group they belonged to.
Subsequent urine and stool samples showed that both groups of coffee drinkers had increased levels of two types of bacteria, and Per Eurekalertthe coffee-consuming group also found increased levels of Firmicutes, a bacterium responsible for “positive emotions in women.”
Psychological studies found that both groups of coffee drinkers also reported lower levels of stress, depression and impulsivity.
However, the beneficial effects of the coffee drinking group were not felt to the same extent. For example, the decaf group saw “significant improvements in learning and memory,” while the caffeine group was the only one to experience reduced anxiety, improved alertness and attention, and a reduced risk of inflammation.
“Our findings reveal the microbiome and neurological responses to coffee, as well as their potential long-term benefits for a healthier microbiome. Coffee may modify the collective actions of microbes and the metabolites they utilize,” states Professor John Cryan, one of the study’s authors. “Coffee is more than just caffeine – it is a complicated dietary factor that interacts with gut microbes, metabolism, and even emotional well-being. Our findings suggest that coffee, whether caffeinated or not, may impact health in different but complementary ways.”
It therefore appears that the beneficial effects of coffee on the gut and brain are not unrelated, but are in fact closely related.
